CharlesKWON
325fe51656
Three correctness bugs in the DML executor that the 4.7 audit
surfaced:
1. RunInsert logged the transaction BEFORE dbAppend() and validation.
LogRecord captured the PREVIOUS row's RecNo, and a CHECK/FK
violation that rolled back via dbDelete() still left a spurious
INSERT entry in the log pointing at the wrong record. Move
LogRecord to after all field puts and all validators pass, so
the log only records committed INSERTs at the correct RecNo.
2. RunUpdate (fallback path) skipped CHECK and FK validation entirely
— only RunInsert validated. An UPDATE could violate the same
constraints INSERT protects against. Add the same validator calls
after FieldPut, with a captured aPrevVals snapshot so the in-
memory record can roll back cleanly on failure. Gated by
SqlLoadConstraints to skip the validator (and its recursive
five_SQL) for tables without SQL-level metadata — tables created
via plain dbCreate see no change.
3. RunDelete had no transaction logging at all — a BEGIN / DELETE /
ROLLBACK cycle silently lost the row. Add LogRecord("DELETE")
before dbDelete so undo can re-surface it. (A full FK-cascade
check on delete would require parent→child scanning; deferred.)
The fast-path SqlBulkUpdate branch still bypasses per-record
validation by design (documented) — it's gated by
`! ::oTxn:IsActive()`, so txn-active queries always take the
validated fallback.
FiveSql2 43/43 (including SAVEPOINT + ROLLBACK TO and all four CHECK/
FK tests), Harbour compat 56/56, Go test ALL PASS.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
FiveSql2 — SQL Engine for Harbour DBF/NTX/CDX
Pratt parser + SQL:1992-2023 full standard support Supports both NTX (Clipper) and CDX (FoxPro/ADS) indexes
Architecture
five_SQL("SELECT ...")
│
├── TSqlLexer Tokenizer
├── TSqlParser2 Pratt parser (data-driven operators)
├── TSqlExecutor Query executor (Volcano model)
│ ├── TSqlAlias Central alias manager (no collisions)
│ ├── TSqlIndex NTX/CDX index optimization (auto-detect)
│ ├── TSqlAgg GROUP BY / aggregation
│ ├── TSqlSort ORDER BY / DISTINCT
│ ├── TSqlDDL CREATE/DROP/ALTER TABLE/INDEX
│ └── TSqlTxn BEGIN/COMMIT/ROLLBACK
├── TSqlExpr AST nodes + expression evaluation
└── TSqlFunc 60+ scalar functions
Build & Test
export PATH="/path/to/harbour-core/bin/linux/gcc:$PATH"
export HB_INSTALL_PREFIX="/path/to/harbour-core"
make # Build all tests
make test # Run all 157 tests
make bench # Parser benchmark
make clean # Clean
SQL Standard Coverage
| Standard | Features | Tests |
|---|---|---|
| SQL:1992 | SELECT, JOIN, GROUP BY, HAVING, Subquery, CASE, CAST | 43 |
| SQL:1999 | CTE, Recursive CTE, Window Functions, MERGE | 10 |
| SQL:2003 | SIMILAR TO, GROUPING SETS, LATERAL, Window frames | 64 |
| SQL:2008 | FETCH/OFFSET, FOR UPDATE, Extended MERGE | (incl.) |
| SQL:2016 | JSON functions, LISTAGG | (incl.) |
| SQL:2023 | ANY_VALUE, GREATEST/LEAST, BOOL_AND/OR | (incl.) |
| Challenge | LeetCode-level complex queries | 15 |
| Extreme | Production analytics stress tests | 15 |
Adding New Operators
Edit TSqlParser2.prg, method InitInfixTables():
::hInfixTT[ TK_MYOP ] := { "<=>", 40, 41, ND_BIN }
One line. No structural changes needed.
Copyright
Copyright (c) 2025-2026 Charles KWON (Charles KWON OhJun) Email: charleskwonohjun@gmail.com All rights reserved.